Ultra low profile surgical stapling instrument for tissue resections

ABSTRACT

A surgical stapling instrument including a stapling end effector configured for unilateral sealing of tissue. The stapling end effector includes an anvil assembly, a cartridge assembly coupled to the anvil assembly such that stapling end effector is movable between open and closed positions; and a clamping member slidably disposed about the anvil assembly and the cartridge assembly between an initial position in which the stapling end effector is in the open position and subsequent advanced positions in which the stapling end effector is in the closed position. The clamping member includes a substantially “C”-shaped cross-section with a leading edge. The leading edge includes a blade portion positioned outwards of the anvil and cartridge assemblies.

FIELD

The disclosure relates to surgical stapling instruments, and, more particularly, to surgical stapling instruments having small diameter stapling end effectors for performing endoscopic tissue resections.

BACKGROUND

Surgical stapling instruments that effect simultaneous dissection and sealing of tissue are well known in the art. Endoscopic surgical stapling instruments for sealing tissue endoscopically through small incisions in the skin or through a cannula rather than by performing open surgical procedures are also well known in the art and have reduced patient trauma.

Typically, linear endoscopic surgical stapling instruments include a stapling end effector that is configured for bilateral sealing of the tissue, i.e., applying at least one row of staples to each side of a knife slot through which a knife passes to cut the sealed tissue. Not all surgical stapling procedures require bilateral sealing of tissue. When bilateral sealing of tissue is not required, the configuration of traditional stapling end effector may be made smaller, more efficient, and/or more cost-effective.

SUMMARY

A stapling end effector includes an anvil assembly, a cartridge assembly coupled to the anvil assembly such that stapling end effector is movable between open and closed positions; and a clamping member slidably disposed about the anvil assembly and the cartridge assembly between an initial position in which the stapling end effector is in the open position and subsequent advanced positions in which the stapling end effector is in the closed position. The clamping member includes a substantially “C”-shaped cross-section with a leading edge. The leading edge includes a blade portion positioned outwards of the anvil and cartridge assemblies.

In aspects of the disclosure, the anvil assembly includes an outer surface defining a channel. The cartridge assembly may include an outer surface defining a channel. The clamping member may include a first edge and a second free edge. The first free edge may include a first flange received within the channel of the anvil assembly and the second free edge may include a second flange received with the channel of the cartridge assembly. The cartridge assembly may include a support member and a staple cartridge. The support member may define a cavity that receives the staple cartridge. The staple cartridge may be removable from the cavity of the support member.

In certain aspects of the disclosure, the cartridge assembly defines a slot and the clamping member includes a protrusion that is received within the slot. The cartridge assembly may include an actuation sled and a plurality of pushers supporting a plurality of staples. The protrusion may be configured to engage the actuation sled when the clamping member moves to the subsequent advanced positions. The blade portion of the clamping member may be positioned adjacent the anvil assembly and the cartridge assembly and may be aligned with a gap defined between the anvil and cartridge assemblies when the stapling end effector is in the closed position. The stapling end effector may include a drive member. The clamping member may include a trailing end and the drive member engages the trailing end.

A surgical stapling instrument includes an elongate body having a distal portion, and a stapling end effector disposed on the distal portion of the elongate body. The stapling end effector includes an anvil assembly, a cartridge assembly coupled to the anvil assembly such that stapling end effector is movable between open and closed positions, and a clamping member slidably disposed about the anvil assembly and the cartridge assembly between an initial position in which the stapling end effector is in the open position and subsequent advanced positions in which the stapling end effector is in the closed position. The clamping member includes a substantially “C”-shaped cross section with a leading edge. The leading edge includes a blade portion positioned outwards of the anvil and cartridge assemblies.

In aspects of the disclosure, the anvil assembly includes an outer surface defining a channel. The cartridge assembly may include an outer surface defining a channel. The clamping member may include first and second free edges. The first free edge may include a first flange received within the channel of the anvil assembly and the second free edge may include a second flange received with the channel of the cartridge assembly. The cartridge assembly may include a support member and a staple cartridge. The support member may define a cavity that receives the staple cartridge. The staple cartridge may be removable from the cavity of the support member.

In certain aspects of the disclosure, the cartridge assembly defines a slot and the clamping member includes a protrusion that is received within the slot. The cartridge assembly may include an actuation sled and a plurality of pushers supporting a plurality of staples. The protrusion may be configured to engage the actuation sled when the clamping member moves to the subsequent advanced positions. The blade portion of the clamping member may be positioned adjacent the anvil assembly and the cartridge assembly and may be aligned with a gap defined between the anvil and cartridge assemblies when the stapling end effector is in the closed position. The stapling end effector may include a drive member. The clamping member may include a trailing end and the drive member engages the trailing end.

The surgical stapling instrument may further include a handle assembly for actuating the stapling end effector. The elongate body and the end effector may have a cross-section with a diameter measuring 5 mm or less.

A surgical stapling instrument includes a handle assembly, an elongate body extending from the handle assembly, and a stapling end effector disposed on a distal portion of the elongate body. The stapling end effector includes stapling end effector includes an anvil assembly, a cartridge assembly coupled to the anvil assembly such that stapling end effector is movable between open and closed positions; and a clamping member slidably disposed about the anvil assembly and the cartridge assembly between an initial position in which the stapling end effector is in the open position and subsequent advanced positions in which the stapling end effector is in the closed position. The clamping member includes a substantially “C”-shaped cross section with a leading edge. The leading edge includes a blade portion positioned outwards of the anvil and cartridge assemblies.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate aspects of the disclosure and, together with a general description of the disclosure given above, and the detailed description given below, explain the aspects of the disclosure, wherein:

FIG. 1 is a perspective side view of a surgical stapling instrument including a stapling end effector according to aspects of the disclosure;

FIG. 2 is an enlarged view of the indicated area of detail of the surgical stapling instrument shown in FIG. 1 including a jaw assembly of the stapling end effector;

FIG. 3 is an enlarged view of the indicated area of detail shown in FIG. 2 including a clamping member of the stapling end effector;

FIG. 4 is a first side perspective view of the clamping member shown in FIG. 3 ;

FIG. 5 is a second side perspective view of the clamping member shown in FIG. 4 ;

FIG. 6 is a perspective side view of the stapling end effector shown in FIG. 1 with the clamping member in a proximal-most position and the jaw assembly in an open or unclamped position, with tissue received between an anvil assembly and a cartridge assembly of the jaw assembly;

FIG. 7 is the perspective side view of the stapling end effector shown in FIG. 6 with the clamping member in a partially advanced position and the jaw assembly of the stapling end effector in a closed or clamped position about the tissue;

FIG. 8 is a cross-sectional end view taken along section line 8-8 shown in FIG. 7 ;

FIG. 9 is a cross-sectional side view taken along section line 9-9 shown in FIG. 8 ;

FIG. 10 is the perspective side view of the stapling end effector shown in FIG. 6 with the clamping member in a further advanced position;

FIG. 11 is a side perspective view of the tissue after the tissue is resected with a sealed section of tissue, i.e., with staple lines, and a non-sealed section of tissue, i.e., without staple lines;

FIG. 12 is a side perspective view of a stapling end effector according to other aspects of the disclosure; and

FIG. 13 is a cross-sectional end view of the stapling end effector shown in FIG. 12 with a clamping member of the stapling end effector in a partially advanced position and a jaw assembly of the stapling end effector in a closed or clamped position.

DETAILED DESCRIPTION

Aspects of the disclosure are described in detail with reference to the drawings, in which like reference numerals designate identical or corresponding elements in each of the several views. As used herein, the term “distal” refers to that portion of the surgical instrument, or component thereof, that is farther from the user during use of the instrument in its customary fashion, while the term “proximal” refers to that portion of the surgical instrument, or component thereof, that is closer to the user during use of the instrument in its customary fashion. As used herein, the term clinician refers to anyone involved in a surgical procedure, including but not limited to, surgeons, support staff, and other medical personnel. Where a numerical limitation is used, unless indicated otherwise by the context, “about” means the numerical value can vary by ±10% and remain within the scope of the disclosure.

Bilateral stapling of tissue requires a stapling end effector configured for applying a first set of staple lines on a first side of a knife slot and second sets of staple lines on a second side of the knife slot. When bilateral stapling is not required, the configuration of the stapling end effector may be rearranged to provide a stapling end effector having a reduced diameter.

FIG. 1 illustrates a surgical stapling instrument 10 including a stapling end effector according to aspects of the disclosure, shown generally as stapling end effector 100. The stapling end effector 100 is supported on a distal end of a small diameter shaft portion 30 of the surgical stapling instrument 10 which extends from a large diameter shaft portion 40 of the surgical stapling instrument 10. The large diameter shaft portion 40 is operably connected to a handle assembly 20 of the surgical stapling instrument 10. In certain aspects of the disclosure, the small diameter shaft portion 30 and the stapling end effector 100 are configured to be received through a five-millimeter (5 mm) access port (not shown). As will be described in detail below, a drive member 50 (FIG. 9 ) extends from the small diameter shaft portion 40 of the surgical stapling instrument 10 and is configured to effect actuation of the stapling end effector 100.

The handle assembly 20 of the surgical stapling instrument 10 includes a stationary grip 22 and a rotation knob assembly 24. Buttons 26 on the stationary grip 22 of the handle assembly 20 allow for actuation of the stapling end effector 100. The rotation knob assembly 24 on the handle assembly 20 permits manual rotation of the shaft portions 30, 40 and stapling end effector 100 by a clinician about a longitudinal axis “x” of the surgical stapling instrument 10. The rotation knob assembly 24 includes an articulation lever 28 for articulating a jaw assembly 102 of the stapling end effector 100 relative to the small diameter shaft portion 30 of the surgical stapling instrument 10.

Although the stapling end effector 100 of the surgical stapling instrument 10 is shown integrally formed with the small diameter shaft portion 30 and large diameter shaft portion 40, it is envisioned that the stapling end effector 100 may be incorporated into a stapler reload (not shown) that is configured for releasable connection of the stapling end effector 100 to either of the small diameter shaft portion 30 or large diameter shaft portion 40 and/or to the handle assembly 20. It is also envisioned that the handle assembly 20 of the surgical stapling instrument 10 may include an adapter assembly (not shown) for releasably connecting the stapling end effector 100 with the handle assembly 20.

The surgical stapling instrument 10 is illustrated as an electrically powered stapling instrument including an electrically powered handle assembly 20 that may support one or more batteries (not shown). Examples of electrically powered surgical stapling instruments can be found in U.S. Pat. Nos. 9,055,943 and 9,023,014. Alternately, it is envisioned that the stapling end effector 100 could also be incorporated into a manual surgical stapling instrument such as disclosed in U.S. Pat. No. 6,238,908 or a stapling instrument that is configured for use with a robotic system, and does not include a handle assembly, such as disclosed in U.S. Pat. No. 9,962,159.

FIGS. 2 and 3 illustrate the stapling end effector 100 of the surgical stapling instrument 10 which includes the jaw assembly 102. The jaw assembly 102 includes an anvil assembly 110 and a cartridge assembly 120 that is pivotal relative to the anvil assembly 110. Although shown with the cartridge assembly 120 being pivotable relative to the anvil assembly 110, it is envisioned that the aspects of the disclosure may be modified for use in a surgical stapling instrument with a stapling end effector having an anvil assembly that pivots relative to a cartridge assembly. A clamping member 130 is slidably positionable about the anvil and cartridge assemblies 110, 120. As will be described in detail below, longitudinal movement of the clamping member 130 about the jaw assembly 102 moves the cartridge assembly 120 between an open or unclamped position (FIG. 6 ) and a closed or clamped position (FIG. 7 ).

The stapling end effector 100 of the surgical stapling instrument 10 will only be described in detail to the extent necessary to fully disclose the aspects of the disclosure. For a detailed description of the structure and function of an exemplary small diameter surgical stapling end effector, please refer to U.S. Pat. No. 10,849,621.

The anvil assembly 110 of the jaw assembly 102 of the stapling end effector 100 of the surgical stapling instrument 10 defines a plurality of staple forming pockets 111 (FIG. 8 ). A channel 113 extends along an outer surface 112 of the anvil assembly 110. The anvil assembly 110 may include a dissecting tip (not shown) or be otherwise configured to engage tissue.

The cartridge assembly 120 of the jaw assembly 102 of the stapling end effector 100 of the surgical stapling instrument 10 includes a support member 122 and a staple cartridge 124 received within the support member 122. More particularly, support member 122 defines a cavity 121 (FIG. 8 ) for receiving the staple cartridge 124. It is envisioned that the staple cartridge 124 may be replaceable to permit reuse of the stapling end effector 100. The support member 122 has an outer surface 122 a that defines a channel 123 (FIG. 8 ) and a slot 125 (FIG. 8 ) that extends through the support member 122 for accessing the staple cartridge 124. Each of the channel 123 and the slot 125 extend along a substantial portion of the length of the support member 122.

The staple cartridge 124 of the cartridge assembly 120 of the stapling end effector 100 supports a plurality of staples “S” (FIG. 8 ) and corresponding staple pushers 126. The staple pushers 126 are configured to eject the plurality of staples “S” from a plurality of staple receiving pockets 127 (FIG. 2 ) as an actuation sled 128 of the cartridge assembly 120 advances through the staple cartridge 124 during actuation of the surgical stapling instrument 10. As shown, the staple cartridge 124 includes three rows of staples. It is envisioned that the staple cartridge 124 may have fewer than three rows of staples “S” or more than three rows of staples “S”.

FIGS. 4 and 5 illustrate the clamping member 130 of stapling end effector 100 of the surgical stapling instrument 10 (FIG. 1 ), including a body 132 having a substantially “C”-shaped cross-section with a leading edge 132 a (FIG. 5 ) and a trailing edge 132 b (FIG. 4 ) and a first edge 132 c and a second free edge 132 d. The first free edge 132 c of the elongate body 132 includes a first flange 134 and the second edge 132 d of the elongate body 132 includes a second flange 136. The first and second flanges 134, 136 extend inwardly towards one another. The first flange 134 is receivable within the channel 113 (FIG. 3 ) in the outer surface 112 of the anvil assembly 110 and the second flange 136 is receivable within the channel 123 (FIG. 9 ) in the support member 122 of the cartridge assembly 120.

The leading edge 132 a of the body portion 132 of the clamping member 130 includes a blade portion 138. The blade portion 138 is configured to be positioned outside of the jaw assembly 102 of the stapling end effector 100 and to align with a space or gap “G” (FIG. 8 ) between the anvil assembly 110 and the cartridge assembly 120 when the anvil and cartridge assemblies 110, 120 are in the clamped position (FIG. 2 ). Although shown as being integrally formed with the body portion 132 of the clamping member 130, it is envisioned that the blade portion 138 of the clamping member 130 may be formed independent of the clamping member 130 and secured to the body portion 132 in any suitable manner.

The body portion 132 further includes a protrusion 140 disposed adjacent the leading edge 132 a. The protrusion 140 is received through the slot 125 (FIG. 8 ) in the support member 122 of the cartridge assembly 120 and is configured to engage the actuation sled 128 of the cartridge assembly 120 as the clamping member 130 is advanced relative to the jaw assembly 102 to advance the actuation sled 128 through the cartridge assembly 120. Although shown to include a single protrusion 140, it is envisioned that the clamping member 130 may include more than one protrusion and the support member 122 may define more than one corresponding slot.

FIG. 6 illustrates the jaw assembly 102 of the stapling end effector 100 in the open position with the cartridge assembly 120 spaced from the anvil assembly 110 to receive tissue “T” between the anvil assembly 110 and the cartridge assembly 120. The clamping member 130 is in a proximal-most position, spaced from the cartridge assembly 120. When the clamping member 130 is in the proximal-most position, the clamping member 130 is disengaged from the cartridge assembly 120, thereby permitting the cartridge assembly 120 to stay in the open position. The jaw assembly 102 may include a spring member (not shown) for maintaining the cartridge assembly 120 in the open position and/or for returning the cartridge assembly to the open position after firing of the surgical stapling instrument 10.

FIG. 7 illustrates the jaw assembly 102 of the stapling end effector 100 in the closed or clamped position, with the tissue “T” clamped between the anvil assembly 110 and the cartridge assembly 120. Advancement of the clamping member 130 to a partially advanced position, as indicated by arrow “A” in FIG. 7 , causes the clamping member 130 to engage the support member 122 of the cartridge assembly 120. Engagement of the support member 122 by the clamping member 130 pivots the cartridge assembly 120 to the clamped position, as indicated by arrow “B”.

FIGS. 8 and 9 illustrate the clamping member 130 in the partially advanced position in which the first flange 134 of the clamping member 130 is received within the channel 113 in the anvil assembly 110 and the second flange 136 of the clamping member 130 is received within the channel 123 of the support member 122 of the cartridge assembly 120. When the clamping member 130 is in the partially advanced position, the protrusion 140 of the clamping member 130 extends through the slot 125 in the support member 122 of the cartridge assembly 120. In the partially advanced position, the protrusion 140 of the clamping member 130 is positioned proximally of and adjacent to the actuation sled 128 of the cartridge assembly 120, as shown in FIG. 9 .

The clamping member 130 is advanced along the longitudinal axis “x” by the drive member 50 (FIG. 9 ). A proximal portion (not shown) of the drive member 50 (FIG. 9 ) is operably connected to the handle assembly 20 (FIG. 1 ) and a distal portion 50 a of the drive member 50 is securely affixed to the clamping member 130 by any suitable means, e.g., welding, adhesive, mechanical fasteners, friction fit. The drive member 50 may be a flexible beam or shaft. The distal portion 50 a of the drive member 50 may engage any portion of the trailing edge 132 b of the body 132 of the clamping member 130. It is envisioned that the distal portion 50 a may be bifurcated. In this manner, the distal portion of the drive member could engage the clamping member 130 at more than one location, e.g., the first and second flanges 134, 136, to provide symmetric loading on the clamping member 130 during actuation to prevent binding of the clamping member 130 as the clamping member 130 is advanced about the jaw assembly 102.

Although the channel 123 and the slot 125 in the support member 122 of the cartridge assembly 120 are shown and described as being separate, it is envisioned that the protrusion 140 of the clamping member 130 may be incorporated into the second flange 136 of the clamping member 130, and the channel 123 may extend completely though the support member 122. In this manner the second flange 136 would operate both to retain the clamp member 130 relative to the cartridge assembly 120 and to engage the actuation sled 128.

FIG. 10 illustrates continued advancement of the clamping member 130 of the stapling end effector 100 about the jaw assembly 102, as indicated by arrow “C”. As the clamping member 130 advances, the clamping member 130 advances the actuation sled 128 to eject the staples from the staple cartridge 124 and cut the tissue “T” positioned in the path of the blade portion 138 of the clamping member 130. The tissue “T” positioned outside of the jaw assembly 102 and the clamping member 130 is not stapled.

After the clamping member 130 of the stapling end effector 100 is fully advanced and the tissue “T” is stapled and cut, the clamping member 130 may be retracted to move the jaw assembly 102 to the open position and release the resected tissue “T”.

FIG. 11 illustrates the resected tissue following the stapling procedure, namely, the sealed tissue “Ts” and the non-sealed tissue or tissue to be removed “Tr”.

As noted above, the staple cartridge 124 of the stapling end effector 100 may be configured for removal and replacement, thereby allowing for reuse of the stapling end effector 100.

FIGS. 12 and 13 illustrate a stapling end effector according to other aspects of the disclosure shown generally as stapling end effector 200. The stapling end effector 200 is substantially the same as the stapling end effector 100 described above except the stapling end effector 200 includes a cartridge assembly 220 with a staple cartridge 228 having a fourth row of staples “S”. The cartridge assembly 220 of the stapling end effector 200 includes staple pushers 226 and an actuation sled 228 configured to accommodate the additional row of staples “S” and an anvil assembly 210 that includes an additional row of staple forming pockets 211 (FIG. 13 ) for forming the additional row of staples “S”. As described above regarding the stapling end effector 100, the stapling end effector 200 includes a clamping member 230 that moves the cartridge assembly 220 between open and closed positions.

Operation of the stapling end effector 200 is same as described above for the stapling end effector 100 and will not be described in further detail herein.

Persons skilled in the art will understand that the instruments and methods specifically described herein and illustrated in the accompanying drawings are non-limiting exemplary aspects of the disclosure. It is envisioned that the elements and features illustrated or described in connection with one exemplary aspect may be combined with the elements and features of another without departing from the scope of the disclosure. As well, one skilled in the art will appreciate further features and advantages of the disclosure based on the above-described aspects. Accordingly, the disclosure is not to be limited by what has been particularly shown and described, except as indicated by the appended claims. 

What is claimed is:
 1. A stapling end effector comprising: an anvil assembly; a cartridge assembly coupled to the anvil assembly such that stapling end effector is movable between open and closed positions; and a clamping member slidably disposed about the anvil assembly and the cartridge assembly between an initial position in which the stapling end effector is in the open position and subsequent advanced positions in which the stapling end effector is in the closed position, wherein the clamping member includes a substantially “C”-shaped cross-section with a leading edge, the leading edge including a blade portion positioned outwards of the anvil and cartridge assemblies.
 2. The stapling end effector of claim 1, wherein the anvil assembly includes an outer surface defining a channel, the cartridge assembly includes an outer surface defining a channel, and the clamping member includes first and second free edges, the first free edge including a first flange received within the channel of the anvil assembly and the second free edge including a second flange received with the channel of the cartridge assembly.
 3. The stapling end effector of claim 1, wherein the cartridge assembly includes a support member and a staple cartridge, the support member defining a cavity that receives the staple cartridge.
 4. The stapling end effector of claim 3, wherein the staple cartridge is removable from the cavity of the support member.
 5. The stapling end effector of claim 1, wherein the cartridge assembly defines a slot and the clamping member includes a protrusion that is received within the slot.
 6. The stapling end effector of claim 1, wherein the cartridge assembly includes an actuation sled and a plurality of pushers supporting a plurality of staples, the protrusion being configured to engage the actuation sled when the clamping member moves to the subsequent advanced positions.
 7. The stapling end effector of claim 1, wherein the blade portion of the clamping member is positioned adjacent the anvil assembly and the cartridge assembly and is aligned with a gap defined between the anvil and cartridge assemblies when the stapling end effector is in the closed position.
 8. The stapling end effector of claim 1, further including a drive member, wherein the clamping member includes a trailing end and the drive member engages the trailing end.
 9. A surgical stapling instrument comprising: an elongate body having a distal portion; a stapling end effector disposed on the distal portion of the elongate body, the stapling end effector comprising: an anvil assembly; a cartridge assembly coupled to the anvil assembly such that stapling end effector is movable between open and closed positions; and a clamping member slidably disposed about the anvil assembly and the cartridge assembly between an initial position in which the stapling end effector is in the open position and subsequent advanced positions in which the stapling end effector is in the closed position, wherein the clamping member includes a substantially “C”-shaped cross-section with a leading edge, the leading edge including a blade portion positioned outwards of the anvil and cartridge assemblies.
 10. The surgical stapling instrument of claim 9, wherein the anvil assembly includes an outer surface defining a channel, the cartridge assembly includes an outer surface defining a channel, and the clamping member includes first and second free edges, the first free edge including a first flange received within the channel of the anvil assembly and the second free edge including a second flange received with the channel of the cartridge assembly.
 11. The surgical stapling instrument of claim 9, wherein the cartridge assembly includes a support member and a staple cartridge, the support member defining a cavity that receives the staple cartridge.
 12. The surgical stapling instrument of claim 11, wherein the staple cartridge is removable from the cavity of the support member.
 13. The surgical stapling instrument of claim 9, wherein the cartridge assembly defines a slot and the clamping member includes a protrusion receivable within the slot.
 14. The surgical stapling instrument of claim 9, wherein the cartridge assembly includes a sled and a plurality of pushers supporting a plurality of staples, the protrusion being configured to engage the sled when the clamping member moves to the subsequent advanced positions.
 15. The surgical stapling instrument of claim 9, wherein the blade portion of the clamping member is positioned adjacent the anvil assembly and the cartridge assembly and is aligned with a gap defined between the anvil and cartridge assemblies when the stapling end effector is in the closed position.
 16. The surgical stapling instrument of claim 9, further including a drive member, wherein the clamping member includes a trailing end and the drive member engages the trailing end.
 17. The surgical stapling instrument of claim 9, wherein the elongate body includes a proximal portion and the proximal portion is configure for operable connection with a handle assembly.
 18. The surgical stapling instrument of claim 9, further including a handle assembly for actuating the stapling end effector.
 19. The surgical stapling instrument of claim 9, wherein the elongate body and the end effector have a cross-section with a diameter measuring 5 mm.
 20. A surgical stapling instrument comprising: a handle assembly; an elongate body extending from the handle assembly, the proximal body having a distal portion; and a stapling end effector disposed on the distal portion of the elongate body, the stapling end effector comprising: an anvil assembly; a cartridge assembly coupled to the anvil assembly such that stapling end effector is movable between open and closed positions; and a clamping member slidably disposed about the anvil assembly and the cartridge assembly between an initial position in which the stapling end effector is in the open position and subsequent advanced positions in which the stapling end effector is in the closed position, wherein the clamping member includes a substantially “C”-shaped cross-section with a leading edge, the leading edge including a blade portion positioned outwards of the anvil and cartridge assemblies. 